California mother, 52, is charged in 1988 cold-case murder of her newborn son who was found dead in a paper bag by two children

  • Lesa Lopez is charged with murder, use of a deadly weapon and great bodily injury in 1988 killing of her baby son 
  • Lopez's newborn, dubbed by investigators Baby Joe Doe, was found in a paper bag discarded along a creek in Castro Valley, California, by two children 
  • Autopsy revealed the baby was alive at birth and was killed
  • Investigators used DNA collected from the scene and genetic genealogy tools to identify Lopez as the alleged killer 
  • Lopez told investigators she was 20 years old at the time and hid her pregnancy  

Lesa Lopez, 52, from California, has been charged with murder, use of a deadly weapon and great bodily injury in the 1988 killing of her baby son, who was found inside a paper bag

Lesa Lopez, 52, from California, has been charged with murder, use of a deadly weapon and great bodily injury in the 1988 killing of her baby son, who was found inside a paper bag 

A California mother has been arrested for the killing of her newborn son, whose body was found stuffed into a bag dumped by a creek 32 years ago in the Bay Area, in a case that was solved thanks to DNA testing and genetic genealogy.

The Alameda County Sheriff's Office said in a statement that 52-year-old Lesa Lopez has admitted to investigators that she was the mother of the slain baby and implicated herself in the 1988 killing.'

'Lopez, who was 20 years old at the time ... told investigators she hid the pregnancy from her family and friends and provided details of what happened,' said sheriff’s Office spokesman Sgt. Ray Kelly.

Lopez, of Salida, was arrested on July 23 and charged with murder, use of a deadly weapon and great bodily injury. She is being held on $2million bail.

Two children playing found the baby’s body on May 15, 1988, inside a paper bag left among trees and bushes on the bank of a creek in Castro Valley. An autopsy revealed the baby was alive at birth and was killed, Kelly said. 

Two children playing in the bushes near a creek in Castro Valley, California (pictured),found the baby's remains in May 1988

Two children playing in the bushes near a creek in Castro Valley, California (pictured),found the baby's remains in May 1988 

The boy, dubbed by investigators as Baby Joe Doe, was given a funeral at St. Leander Church in San Leandro attended by more than 200 people. A priest posthumously named him Richard Jayson Terrance Rein after the church’s vicars and priests.

In 2005, the DNA of a woman, believed by investigators to be that of the baby's mother, was found in evidence collected from the crime scene and submitted to to CODIS, the national DNA database used by law enforcement, but it did not produce a match.

Multiple investigators with the sheriff’s office tried to solve the case over the last 32 years 'for a baby boy who never had a voice and never had the chance of living a full life,' Kelly said.

Last year, investigators again took up the case with the help of experts in forensic genetic genealogy from the FBI and private labs, including Oklahoma-based DNA Solutions and Gene By Gene, which owns the genealogy website FamilyTreeDNA.

After extensive genealogy research, surveillance and DNA 'surreptitiously obtained' from Lopez’s discarded trash, cold-case investigators linked Lopez to the crime scene, Kelly said.

Lopez's baby son, posthumously named Richard Jayson Terrance Rein, was given a funeral at St. Leander Church in San Leandro attended by more than 200 people

Lopez's baby son, posthumously named Richard Jayson Terrance Rein, was given a funeral at St. Leander Church in San Leandro attended by more than 200 people

They used the same advanced DNA testing that helped crack the decades-old Golden State Killer case. In 2018, police investigators identified Joseph DeAngelo Jr., a former police officer, after using DNA from crime scenes to find relatives of their suspect through a popular genealogy website database. 

They tailed DeAngelo and secretly collected DNA from his car door and a discarded tissue to get an arrest warrant. DeAngelo, who terrorized California as a serial burglar and rapist and went on to kill more than a dozen people while evading capture for decades, pleaded guilty last month.

Genetic geneologist Dr Barbara Rae-Venter, who helped identify DeAngelo as the Golden State Killer, also assisted in Lopez's case. 

Santa Rita Jail records indicate that Lopez is due in court for a plea hearing on Wednesday.